In centrifugal separators provided with a shaft suspension device of this kind the elastical element acts with a well defined radially inwardly directed spring force, which during operation strives to bring the composed unit back to a central position and damps effectively the oscillating movements of it, which can be very critical during the passage of critical number of revolutions or when heavy unbalances occur during operation. Furthermore, bearing devices of this kind often are cheaper than alternative possible solutions.
In some centrifugal separators you need to be able to supply during operation a liquid under pressure to a member forming a part of the composed unit. One example when you need this is centrifugal separators, which demand an effective cooling of the bearings. Another example is centrifugal separators, in which a gap between a stationary part and a part oscillating during operation is sealed by means of a liquid gap sealing. A third example is centrifugal separators journally supported hydraulically, in which rotating parts are supported by a carrying oil film. However, in this case the flow passage has to be throw flown by a small amount of oil, which corresponds to the amount of oil, which leaves the hydraulic bearing through leakage or the like.